On June 10, on a 500kV transmission grid in Shangri-La, Yunnan, technicians completed the live installation of the integrated sensing system, and successfully collected the monitoring data including the wire current and temperature on the cloud platform. It symbolized that the world first panoramic intelligent monitoring system of transmission line jointly developed by the Department of Electrical Engineering and Applied Electronics of Tsinghua University, Tsinghua Sichuan Energy Internet Research Institute and the Digital Grid Research Institute of China Southern Power Grid was successfully put into operation. CCTV gave a live broadcast of the whole installation process.

Photo: The world first panoramic intelligent monitoring system of power transmission was successfully put into operation (Source: CCTV News)

With the advancement of smart grid construction and the development of artificial intelligence technology, transmission line inspection has transitioned from the traditional "manual inspection" to the "manual inspection + machine inspection". However, operation and maintenance are still vulnerable to weather and other factors, and involved with high work intensity and technical difficulty, while most online monitoring devices and restricted by isolated function and information. Taking the power transmission line Shangri-La as an example, where the average altitude is above 3000 meters, the weather is complex and changeable and the terrain is rugged, both manual and UAV transmission line maintenance means are subject to objective conditions, operation and maintenance are difficult, and there are hidden dangers to the safe operation of transmission lines.

It's a major difficulty for scientific researchers that how to monitor power transmission lines online in real time, and comprehensively analyze the judge the line state through intelligent sensing by multiple integrated sensors, and remotely transmitting the panoramic information of the line to the cloud platform. The energy sensing team composed of Professor He Jinliang, Associate Professor Hu Jun from the Department of Electrical Engineering and Applied Electronics of Tsinghua University, and researchers from Tsinghua Sichuan Energy Internet Research Institute, has constituted a panoramic intelligent monitoring system for transmission lines through an integrated, intelligent and self-powered solution based on advanced micro-sensors, which can assess the operation state, insulation characteristics and the external disaster climate in real time, and forecast and accurately position any defect or fault risk.

Compared with the current online monitoring system with many discrete and single sensors, the panoramic intelligent monitoring system can realize effective integration and information fusion at the sensor level, and the real-time digital panoramic monitoring of the transmission line state, which fully meets the requirement for digitalization of smart grid.

The panoramic intelligent monitoring system for power transmission lines, integrated with the micro-wideband and large-range electrical parameter sensor chips independently developed by the Department of Electrical Engineering and Applied Electronics of Tsinghua University, as well as miniaturized multi-parameter sensors for mechanics, displacement, vibration, galloping, temperature and so on, is an "Omni-Keeper" integrated with functions for line operation state and surrounding environment monitoring and early warning. This system can monitor the operating temperature, steady-state and transient current of the transmission line in real time, quickly make judgments on abnormal conditions such as various line faults; record the line vibration frequency, amplitude, trajectory and other data, monitor the line galloping and ice accumulation in real time, and judge the impact of strong winds and ice disasters on transmission lines; sense changes in the ambient temperature, humidity and pressure, etc in real time, dynamically monitor the current operating weather conditions of the transmission line, and the surrounding environment images of the transmission line, and give early warnings against any disaster such as fire or landslide. The system can wirelessly transmits the data information collected by the sensing devices to the monitoring center in real time, replace the traditional manual line inspection, and reduce the frequency of transmission line maintenance from once per month manually to 24-hour real-time monitoring, which significantly reduces the line maintenance cost, and improve the operation reliability.

Relying on the technology accumulation of the Department of Electrical Engineering and Applied Electronics of Tsinghua University for more than 10 years and focusing on the development of micro-sensing chips, smart sensor devices and energy digitization technologies, the energy sensing team has successively overcome technical difficulties in continuous collection of environmental micro-energy, non-contact perception, edge intelligent recognition and equipment integration, and applied the related achievements to grid monitoring and smart power equipment. The successful operation of the panoramic intelligent monitoring system for transmission lines will provide reliable guarantee for the intelligent maintenance and safe operation of power transmission lines. In the future, the team will develop more advanced smart sensors and perception technologies for grids and equipment to satisfy the demand for digitalized smart grid construction and comprehensively support the new power system centered at new energies.